The semiconductor layers of semiconductor chips, for example the radiation-generating layer structures of radiation-emitting and of radiation-receiving semiconductor chips, can be defined by a multiplicity of different epitaxy methods, such as metal organic vapor phase epitaxy (MOVPE), molecular beam epitaxy (MBE), liquid phase epitaxy (LPE), etc. As an alternative or in a supplementary manner, such layer structures may at least partly be defined by indiffusion of dopants.
Both epitaxy processes and doping processes are subject to certain manufacturing fluctuations. In the case of light-emitting semiconductor chips, manufacturing fluctuations often lead to fluctuations in the brightness of semiconductor chips that are nominally of identical type, during operation. Both the wafers that are produced in different epitaxy process runs and the various wafers that are produced simultaneously in one process run are subject to manufacturing fluctuations, the fluctuations within the wafers produced in one process run being smaller.